JPH06122282A - Thermal transfer record medium - Google Patents

Abstract

PURPOSE:To obtain a thermal transfer record medium with which sticking phenomenon and abrasion of a thermal head do not occur, having excellent conveying property at recording thermally, and having a backing layer which can be coated with water paint. CONSTITUTION:A thermal transfer record medium comprises a thermal transfer color material layer formed on one face of a film support body and a backing layer formed on other face. A water soluble resin and a water soluble lubricant are added to the backing layer. Particularly, silicone modified polyvinyl alcohol is excellent for the water soluble resin and a water soluble silicone oil is excellent for the water soluble lubricant.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a thermal transfer recording medium having a backing layer capable of preventing a sticking phenomenon, having good running property at the time of thermal transfer, and capable of being coated with water.

[0002]

2. Description of the Related Art In a thermal transfer recording medium using a polymer film such as polyethylene terephthalate as a film support, a part of the film support is thermally melted and fused to a thermal head during thermal recording (sticking phenomenon). There is.

The sticking phenomenon significantly deteriorates the recording quality, and in the worst case, the film support burns on the thermal head, making it impossible to run the thermal transfer recording medium. As a technique for preventing such sticking phenomenon, there is a technique for forming a backing layer.

For example, Japanese Patent Laid-Open No. 55-7467 proposes to provide a heat resistant protective film such as a silicone resin on a film support. However, since the friction with the thermal head is large, thermal recording is difficult when recording for a long time. The drawback is that the head wears.

Further, JP-A-57-129789 proposes to provide a resin layer containing a surfactant or organic salt which is solid or semi-solid at room temperature on a film support. Since it is formed by solvent coating or by curing the monomer or oligomer after coating, consideration for environmental hygiene and work safety in the coating process is required, or equipment for polymerizing and curing the coating layer is required. There were defects and inconveniences such as doing.

Further, JP-A-60-94390 proposes a backing layer composed of a water-soluble resin and a fluorosurfactant. Although a water-based coating is possible and sticking can be prevented, the slipping property of the backing layer is low. Is not sufficient, and sufficient runnability of the thermal transfer recording medium during recording cannot be obtained.

[0007]

SUMMARY OF THE INVENTION An object of the present invention is to provide a backing layer which can prevent sticking phenomenon, does not wear the thermal head, has sufficient running property during thermal recording, and can be water-based coated. It is to provide a thermal transfer recording medium.

[0008]

That is, the present invention provides a thermal transfer recording medium having a heat-sensitive transfer coloring material layer on one surface and a backing layer on the other surface of a film-like support, and a water-soluble resin and a water-soluble resin as the backing layer. A thermal transfer recording medium characterized by containing a hydrophilic lubricant.

As the water-soluble resin used in the present invention,
For example, there are the following. Gelatin, gelatin derivatives, casein, proteins such as albumin, carboxymethyl cellulose, methyl cellulose, cellulose derivatives such as ethyl cellulose, polysaccharides such as dextrin, gum arabic, polyvinyl alcohol,
Water-soluble polyvinyl acetals such as polyvinylpyrrolidone and polyvinyl butyral.

Of the above, silicone-modified polyvinyl alcohol is particularly preferred. The softening point (measured by the ring and ball method) of the water-soluble resin used in the present invention is 12
A temperature of 0 ° C or higher is preferable.

As the water-soluble lubricant used in the present invention,
For example: Alcohol-modified silicone oil, water-soluble silicone release agent, polyether change silicone oil, etc.

Particularly preferable among the above are alcohol-modified silicone oil and water-soluble silicone release agent.

The composition ratio of the water-soluble resin and the water-soluble lubricant in the backing layer of the present invention is not limited, but the weight ratio is preferably 100: 1 to 100: 30. If the amount of the water-soluble lubricant is less than this weight ratio, the runnability of the thermal transfer recording medium at the time of thermal recording is deteriorated due to the decrease in lubricity, and if it is more than the weight ratio, the migration of the water-soluble lubricant to the ink layer in the wound product increases. It causes printing defects.

The film-like support used in the present invention may be a resin film having excellent surface smoothness and dimensional stability, and resin films such as polyethylene terephthalate film, polyethylene naphthalate film, polyimide film and polycarbonate film can be used. It can be mentioned as a specific example.

The thickness of the film-like support is preferably 3 to 15 μm. In order to enhance the adhesiveness of the backing layer of the present invention, these supports have corona discharge, glow discharge,
Other treatments such as electron impact flame treatment, ultraviolet irradiation, oxidation treatment, saponification treatment and surface roughening may be carried out, or subbing processing may be carried out.

The method of coating the backing layer of the present invention on the film support may be arbitrary, but wire bar coating, gravure coater coating, reverse roll coater coating, extrusion coater coating and the like may be used. Backing layer thickness is 0.01
To 2 μm is preferable, and 0.01 to 0.5 μm is particularly preferable.
Is. If it is thinner than this, it is difficult to obtain a uniform backing layer, and if it is thick, the thermal sensitivity is lowered.

In the present invention, the color material layer may be of any known type, and may be a so-called melt transfer type or sublimation transfer type. The color material layer of the present invention only needs to contain at least a coloring agent, and the colorant may be any pigment such as a known pigment or dye.

When the color material layer of the present invention is constructed as a melt transfer type, the color material layer may be composed of two or more layers,
It may have other layers such as an undercoat layer and an intermediate layer. Known techniques can be referred to for forming the color material layer, such as the method of applying the color material layer and the types of additives. The thickness of the color material layer of the present invention is not limited, and may be, for example, about 2 to 5 μm.

[0019]

EXAMPLES Hereinafter, the present invention will be specifically described with reference to examples. In the following description, the amount (part) of each component is part by weight.

Example 1 A mixture having the following composition was separately pulverized and dispersed for 2 days using a magnetic ball mill to prepare a backing layer coating solution [A]. [Solution A] 10% aqueous solution of methylcellulose 100 parts Alcohol-modified silicone oil (SF8427 manufactured by Toray Dow Corning Silicone Co., Ltd.) 1.5 parts Water 300 parts

Next, this [solution A] was coated on one surface of a polyethylene terephthalate film having a thickness of 4.5 μm so that the dry adhesion thickness would be 0.5 μm. Then, the other surface of the above-mentioned polyethylene terephthalate film is coated with a coating liquid for a heat-meltable colorant layer having the following composition and dried to a thickness of 3 μm.
A thermal transfer recording medium (a) of the present invention was obtained by providing a m color material layer. [Coating liquid for color material layer] Paraffin (melting point 64 ° C) 50 parts Carnauba wax 25 parts Ethylene-vinyl acetate copolymer 10 parts Carbon black 15 parts

(Example-2) Except that the following [solution B] was used instead of [solution A] in example-1,
A thermal transfer recording medium (b) was obtained in the same manner as. [Liquid B] 100% 10% aqueous solution of polyvinyl alcohol Water-soluble silicone release agent (SH7090 manufactured by Toray Dow Corning Silicone Co., Ltd.) 5 parts Water 300 parts

(Example-3) All of Example-1 except that the following [solution C] was used instead of [solution A] of example-1.
A thermal transfer recording medium (c) was obtained in the same manner as. [C liquid] 10% aqueous solution of silicone-modified polyvinyl alcohol 100 parts (Kuraray Co., Ltd. R-2105) Alcohol-modified silicone oil 20 parts (Toray Dow Corning Silicone SF8427) Water 300 parts

Comparative Example-1 A thermal transfer recording medium (d) was obtained in the same manner as in Example-1, except that sodium dodecylbenzenesulfonate was used in place of the alcohol-modified silicone oil in Example-1.

(Comparative Example-2) Except that the alcohol-modified silicone oil was excluded from Example-1, all other examples-
A thermal transfer recording medium (e) was obtained in the same manner as in 1.

The thermal transfer recording media (a) to (e) obtained in the above-mentioned Examples and Comparative Examples were printed by a thermal transfer simulator manufactured by Okura Electric Co., Ltd. under the following conditions, and the presence or absence of stains and sticking on the head, The quality of transportability was evaluated. The results are shown in Table 1. Thermal head ： Kyocera KMT head pressure ： 300g / cm Ribbon tension tension ： 1400g ・ cm Printing speed ： 2 inch / sec Printing energy ： 30mj / mm ² Applied pulse ： All line continuous 320 pulse

[0026]

[Table 1]

(Note) Criteria for determination in Table 1 Stain of head Yes: When continuous printing is performed for 1 km, dust adherence is observed on the summer head. No: No dust is observed on the summer head even after continuous printing for 1 km. With sticking: Sticking occurs under this printing condition. None: Does not occur. Conveyability Good: No problem Somewhat bad: Sometimes conveyance does not go smoothly. Defective: Not transported at all.

[0028]

As described above, according to the present invention, it is possible to obtain a thermal transfer recording medium which is free from head contamination and sticking, has good transportability, and has no problem in head wear.

Claims (3)

[Claims] 1. A thermal transfer recording medium having a heat-sensitive transferable coloring material layer on one surface of a film-like support and a backing layer on the other surface, wherein the backing layer contains a water-soluble resin and a water-soluble lubricant. Characteristic thermal transfer recording medium. 2. The thermal transfer recording medium according to claim 1, wherein the water-soluble resin is a silicone-modified polyvinyl alcohol. 3. The thermal transfer recording medium according to claim 1, wherein the water-soluble lubricant is a water-soluble silicone oil.